30 research outputs found
SURFACE TREATMENT AND EXAMINATION OF GRADE 2 AND GRADE 5 TITANIUM
Surface characteristics play an important role in the implant-bone integration that is required for the long-term reliability of dental and orthopedic implants. In this paper, we investigate the effect of acid etching on the mass reduction and roughness of grade 2 and grade 5 Ti under controlled experimental conditions. Three different etching compounds were investigated: 30% HCl, 85% H3PO4 and the compound of 30% (COOH)2 × 2H2O and 30% H2O2 in various treatment intervals under controlled temperature. Stereo microscopy, scanning electron microscopy, roughness and weight measurements were carried out on the samples. We found that neither 85% H3PO4 nor the compound of 30% (COOH)2 × 2H2O and 30% H2O2 were able to remove the machining marks from the surface of Ti discs in our experimental setting. On the other hand, etching in 30% HCl yielded even surfaces both on Ti grade 2 and 5 discs. We also found that etching at higher temperatures in 30% HCl resulted in significant mass loss
Phasic affective signals by themselves do not regulate cognitive control
Cognitive control is a set of mechanisms that help us process conflicting stimuli and maintain goal-relevant behaviour. According to the Affective Signalling Hypothesis, conflicting stimuli are aversive and thus elicit (negative) affect, moreover – to avoid aversive signals – affective and cognitive systems work together by increasing control and thus, drive conflict adaptation. Several studies have found that affective stimuli can indeed modulate conflict adaptation, however, there is currently no evidence that phasic affective states not triggered by conflict also trigger improved cognitive control. To investigate this possibility, we intermixed trials of a conflict task and trials involving the passive viewing of emotional words. We tested whether affective states induced by affective words in a given trial trigger improved cognitive control in a subsequent conflict trial. Applying Bayesian analysis, the results of four experiments supported the lack of adaptation to aversive signals, both in terms of valence and arousal. These results suggest that phasic affective states by themselves are not sufficient to elicit an increase in control
SURFACE TREATMENT AND EXAMINATION OF GRADE 2 AND GRADE 5 TITANIUM
Surface characteristics play an important role in the implant-bone integration that is required for the long-term reliability of dental and orthopedic implants. In this paper, we investigate the effect of acid etching on the mass reduction and roughness of grade 2 and grade 5 Ti under controlled experimental conditions. Three different etching compounds were investigated: 30% HCl, 85% H3PO4 and the compound of 30% (COOH)2 × 2H2O and 30% H2O2 in various treatment intervals under controlled temperature. Stereo microscopy, scanning electron microscopy, roughness and weight measurements were carried out on the samples. We found that neither 85% H3PO4 nor the compound of 30% (COOH)2 × 2H2O and 30% H2O2 were able to remove the machining marks from the surface of Ti discs in our experimental setting. On the other hand, etching in 30% HCl yielded even surfaces both on Ti grade 2 and 5 discs. We also found that etching at higher temperatures in 30% HCl resulted in significant mass loss
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Is there evidence for cross-domain congruency sequence effect? A replication of Kan et al. (2013)
Exploring the mechanisms of cognitive control is central to understanding how we control our behaviour. These mechanisms can be studied in conflict paradigms, which require the inhibition of irrelevant responses to perform the task. It has been suggested that in these tasks, the detection of conflict enhances cognitive control resulting in improved conflict resolution of subsequent trials. If this is the case, then this so-called congruency sequence effect can be expected to occur in cross-domain tasks. Previous research on the domain-generality of the effect presented inconsistent results. In this study, we provide a multi-site replication of three previous experiments of Kan et al. (Kan IP, Teubner-Rhodes S, Drummey AB, Nutile L, Krupa L, Novick JM 2013 Cognition 129, 637-651) which test congruency sequence effect between very different domains: from a syntactic to a non-syntactic domain (Experiment 1), and from a perceptual to a verbal domain (Experiments 2 and 3). Despite all our efforts, we found only partial support for the claims of the original study. With a single exception, we could not replicate the original findings; the data remained inconclusive or went against the theoretical hypothesis. We discuss the compatibility of the results with alternative theoretical frameworks
Differential expression of the brassinosteroid receptor-encoding BRI1 gene in Arabidopsis
Abstract Brassinosteroid (BR)-regulated growth and
development in Arabidopsis depends on BRASSINOSTEROID
INSENSITIVE 1 (BRI1), the BR receptor that
is responsible for initiating the events of BR signalling.
We analysed the temporal and spatial regulation of BRI1
expression using stable transgenic lines that carried BRI1
promoter:reporter fusions. In both seedlings and mature
plants the tissues undergoing elongation or differentiation
showed elevated BRI1 gene activity, and it could be
demonstrated that in the hypocotyl this was accompanied
by accumulation of the BRI1 transcript and its receptor
protein product. In seedlings the BRI1 promoter was also
found to be under diurnal regulation, determined primarily
by light repression and a superimposed circadian control.
To determine the functional importance of transcriptional
regulation we complemented the severely BR insensitive
bri1-101 mutant with a BRI1-luciferase fusion construct
that was driven by promoters with contrasting specificities.
Whereas the BRI1 promoter-driven transgene fully restored the wild phenotype, expression from the photosynthesisassociated
CAB3 and the vasculature-specific SUC2 and
ATHB8 promoters resulted in plants with varying morphogenic
defects. Our results reveal complex differential regulation
of BRI1 expression, and suggest that by influencing
the distribution and abundance of the receptor this regulation
can enhance or attenuate BR signalling
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Registered replication report: a large multilab cross-cultural conceptual replication of Turri, Buckwalter, & Blouw (2015)
According to the Justified True Belief account of knowledge (JTB), a person can only truly know something if they have a belief that is both justified and true (i.e., knowledge is justified true belief). This account was challenged by Gettier (1963), who argued that JTB does not explain knowledge attributions in certain situations, later called Gettier-type cases, wherein a protagonist is justified in believing something to be true, but their belief was only correct due to luck. Lay people may not attribute knowledge to protagonists with justified but only luckily true beliefs. While some research has found evidence for these so-called Gettier intuitions (e.g., Machery et al., 2017a), Turri et al. (2015) found no evidence that participants attributed knowledge in a counterfeit-object Gettier-type case differently than in a matched case of justified true belief. In a large-scale, cross-cultural conceptual replication of Turri and colleagues’ (2015) Experiment 1 (N = 4,724) using a within-participants design and three vignettes across 19 geopolitical regions, we did find evidence for Gettier intuitions; participants were 1.86 times more likely to attribute knowledge to protagonists in standard cases of justified true belief than to protagonists in Gettier-type cases. These results suggest that Gettier intuitions may be detectable across different scenarios and cultural contexts. However, the size of the Gettier intuition effect did vary by vignette, and the Turri et al. (2015) vignette produced the smallest effect, which was similar in size to that observed in the original study. Differences across vignettes suggest epistemic intuitions may also depend on contextual factors unrelated to the criteria of knowledge, such as the characteristics of the protagonist being evaluated